Bloc Loc Half Square Triangle Ruler Set 1 - HST-Set#1Half Square Triangle Set #1 includes the 1 1 2", 2 1 2", 3 1 2", 4 1 2", 5 1 2" and 6 1 2" multiple sized rulers. Each ruler locks onto the seam for instant ruler placement and control so that the seams end in each corner. Trims 90% faster than a flat ruler and the ruler rock is gone, too. Also trims quarter square triangles, birds in the air, y units, LeMoyne Star, double windmill, hidden squares and much, much more! Includes 1 8" increments.